Objective: In this study, we investigated the relationship between chronic low back pain and bone mineral density in a young and middle-aged male population. Materials and Methods: A total of 104 male patients with chronic low back pain were enrolled in the study. All subjects completed the Oswestry Disability Index (ODI). Additionally, the intervertebral disc degeneration (DD) was graded according to the Thompson's classification. After bone mineral density was measured the patients were divided into two groups: normal (n=50) and low (n=54) bone density groups. In addition, for comparing the data of patient sub-groups, bone mineral density was measured in 30 healthy subjects. Results: T and Z-scores of the L2 -L4 and the femoral neck were found to be significantly lower in the patient group compared to the control group. In the patient group, there was a positive correlation between the ODI score and the DD score. There were negative correlations between both the ODI score and the DD score and L2-L4 and femoral neck T scores and Z-score. The DD and ODI scores were found to be significantly higher in a patient with low bone density compared to a patient with normal bone density. Conclusion: We think that the low bone mineral density in young and middle-aged male patients with chronic lower back pain is related to disability and physical inactivity. Key Words: Chronic low back pain; lumbar disc degeneration; bone mineral density; physical inactivity; disability; male Amac: Bu calismada genc ve orta yas erkek populasyonunda kronik bel agrisi ve kemik mineral yogunlugu arasindaki iliski incelenmistir. Gerec ve Yontem: Calismaya alinan kronik bel agrili toplam 104 erkek hasta Oswestry Disability Index (ODI) sorgulama formunu doldurdu. Ayrica, intervertebral disk dejenerasyonu Thompson's klasifikasyonuna gore derecelendirildi. Hastalar kemik mineral yogunlugu (KMY) olculdukten sonra normal kemik dansiteli (n=50) ve dusuk kemik dansiteli (n=54) olmak uzere iki gruba ayrildi. Ek olarak hasta alt gruplarinin verileri ile karsilastirilmak uzere 30 sagliklida da KMY olcumu yapildi. Bulgular: L2-L4 ve femur boynu T ve Z skorlari, hasta grubunda kontrol grubuna kiyasla anlamli derecede daha dusuk olarak bulundu. Hasta grubunda, ODI skoru ve DD skoru arasinda pozitif korelasyon vardi. Hem ODI skoru hem de DD skoru ile L2-L4 ve femur boynu T ve Z skorlari arasinda negatif korelasyonlar vardi. DD ve ODI skorlari normal kemik dansiteli hasta ile kiyaslandiginda, dusuk KMY'li hastada anlamli derecede daha yuksek olarak bulundu. Sonuc: Biz, kronik bel agrili genc ve orta yas erkek hastalardaki dusuk KMY'nin, fiziksel aktivite azligi ve yetersizlige bagli oldugunu dusunuyoruz. Anahtar Kelimeler: Kronik bel agrisi; lomber disk dejenerasyonu; kemik mineral yogunlugu; fiziksel inaktivite; ozurluluk; erkek